Scaling laws are a useful way to characterize fluid flow over a wide range of flow rates and experimental conditions. Theorists now explain several earlier experiments by finding a scaling law that describes how a liquid-liquid interface changes shape when driven by viscous forces.

High-intensity x-ray measurements show how suspended particles in a narrow channel are attracted to—or repelled from—the channel walls depending on the ionic concentration of the suspension. These results could have implications for the design of nanofluidic devices.